Sand Jackal Run Waypoint — , head northeast and use the Jackal to enter the first Sand Portal. Continue north and interact with a second Sand Portal to be teleported onto a ledge just south of the center of the Mouth of Torment. From here you can see the mastery insight on another floating ledge in the distance. Switch to using a Griffon. Simply fly over to the mastery insight.

Other methods

If you have the Bond of Faith mastery, you can easily get there after the second jackal Sand Portal by using the Springer to jump, then gliding forwards.

With Springer mount tier 3, jump to the top of the spire at the exit of the second jackal Sand Portal. Dismount, and use the height advantage to either glide to the platform or use a Jackal's blink.

Sand Portals can be avoided altogether via the usage of a Springer (also with the third mastery tier unlocked). Jump out of the Forged fortifications below, to arrive at the exit of the second Sand Portal described above. The Springer can then be used to jump onto the stalagmite behind the Sand Portal, using the lower rocks to get on top of it. With leaning, a glider can then be used to glide over to the mastery insight.

If you have the Griffon, regardless of how many masteries for it, you can simply fly north off of the top floor of the Djinn Enclave.